Imaging examination methods allow a doctor or radiologist to be able to diagnose a plurality of patient diseases. Many diseases require special examination methods in order to ensure a reliable diagnosis. Imaging diagnosis is gaining increasing importance particularly with the treatment of vascular diseases but also with tumor treatment. With the diagnosis and therapy of arteriosclerosis, it is desirable for instance to be able to quantitatively determine the plaques developing in a vascular system of a patient and which result in arteriosclerosis. It was previously only possible to control individual plaques during the temporal course.
While simple narrowing of the vessel (stenosis) can be identified comparatively easily in angiography, diseases, in which only one pathological change in the vascular wall is present, but still no stenosis, can only be diagnosed when a damaging event has taken place. This is the case for instance if the innermost layer of the vascular wall (intima) has peeled away and has blocked the vessel.
A visualization using the known magnetic resonance tomography (MR) methods is possible with the so-called vulnerable plaques. It is known to use specially prepared iron oxide particles (Very Small Iron Oxide Particles, VSOP; Ultra Small Iron Oxide Particle, USPIO) or Gd- or F-marked liposomes as the contrast agent. The contrast agent can be coupled here to plaque-specific ligands (e.g. uPA, RGD), so that they accumulate in the plaques. A high measurement resolution is needed in order to identify the VSOP accumulation due to the signal deletion and the generally minimal accumulation of the iron oxide content, thereby resulting in long measurement times. A complete examination of a patient is thus generally not possible due to time constraints. The same applies to the use of marked liposomes, which likewise only accumulate to a minimum degree.
On the other hand, it is known to detect the blood flow within a vascular tree by means of numerical simulations. To this end, the shape of the vascular tree has to be known, which may therefore result for instance from a segmented angiography (based on an MR or CT measurement). One example of a method of this type has been described by Frauenfelder et al. in “Flow and wall shear stress in end-to-side and side-to-side anastomosis of venous coronary artery bypass grafts”, BioMedical Engineering OnLine 2007, 6:35. Methods, in which the interior of a vessel is examined using a catheter, are likewise known. Further methods for determining the blood flow dynamics are the optical coherence tomography, intravascular ultrasound and near-infrared fluorescence diagnostics.